Currently, the home automation for automatically controlling home appliances at home or at a remote place has been almost commercialized. In case of the initial-stage home automation, the respective appliances are separately controlled using telephones or infrared rays without interconnection between the appliances. At present, a network is constructed among the appliances using a communication means, and a controller for controlling the network is provided to manage the appliances in integration.
Microcomputers applied to the appliances have a built-in serial communication function, and can communicate with other microcomputers or appliances. This microcomputer has diverse sizes of resources that can be used in communications such as a memory according to the characteristic of the appliance. In case of multimedia products such as personal computers (PCs), television receivers (TVs), audio appliances, etc., high-performance hardware specifications are adopted to operate diverse basic functions, and the communication standard for processing a large amount of data at a high speed is required.
On the contrary, in case of refrigerators, washing machines, microwave ovens, lamps, gas alarms, desk lamps, boilers, etc., their functions are very simple in comparison to the above-mentioned PCs or multimedia products, and thus a low-performance microcomputer of 8 bits or less is generally used. In case of the home appliances adopting the low-performance microcomputer, the basic remote control or monitoring of the operation state is the main object of the communications, and thus the communication standard using small-sized microcomputer resources is required.
However, in case of the communication protocols being currently used or proceeding for the purpose of communications between the appliances, separate communication modules such as modems are additionally installed in the respective appliances in order to use the high-performance communication standard applied to the PCs or multimedia appliances as it is, or the high-performance communication standard is partially modified.
The conventional home appliances adopt the high-performance communication standard used in the PCs or multimedia appliances, and thus have the problems of inefficiency and increase of cost due to the adoption of the unnecessary communication standard higher than their actual functions since a separate hardware communication module such as a modem is to be additionally installed in each appliance.